Question

An alternating e.m.f. is applied to purely capacitive circuit. The phase relation between e.m.f. and current flowing in the circuit is or
In a circuit containing capacitance only

• A. e.m.f. is ahead of current by $\frac{\pi }{2}$
• B. Current is ahead of e.m.f. by $\frac{\pi }{2}$
• C. Current lags behind e.m.f. by $\pi$
• D. Current is ahead of e.m.f. by $\pi$

Answer 1

The correct option is B Current is ahead of e.m.f. by $\frac{\pi }{2}$

For purely capacitive circuit $e=e_{0}sin\omega t$
$i=i_{0}sin(\omega t+\frac{\pi }{2})$ i.e., current is ahead of emf by $\frac{\pi }{2}$